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Power Management Power Management
Figure 3: LDO regulators.
helps to balance heat dissipation and wear level. cant power consumption decrease. But if it is not
Figure 1: Wisebatt Schematic.
One can expect to reach 1,5x the initial battery life enough, a bigger battery should be considered.
PERFORMANCE The use of buck regulators can lead to similar when compared to a single power domain. This choice should be made only when no other
The first criterion that motivates any design change battery life improvements. Yet, buck regulators option is possible, as it might imply significant
is the optimization gain: how much additional might not be adapted to all use cases as they Finally, a simple strategy is to use a load switch in changes in the product characteristics.
battery life could one achieve with each strategy? might introduce a lot of noise on the power sup- order to shut down all the unused components in
Some simple design adjustments can provide great ply due to their switching frequency. the system. It can lead to a gain of at least +10%
results. One should start by powering down unused of battery life (depending on the device’s applica- COST
peripherals to minimize power consumption and The addition of another LDO regulator to tion and the components that are shutdown). The selection of a specific power management
leakage. In fact, small savings added together can noise-sensitive components such as sensors or strategy also depends on its impact on the de-
extend the battery life up to 2.5 times. radios can fix this shortcoming. When buck regu- With these strategies, one can achieve a signifi- vice’s final price. Indeed, changes in the design
lators cannot be used, splitting the power domain
Figure 2: Buck regulators. Figure 4: Simulation.
56 MAY 2021 | www.powerelectronicsnews.com MAY 2021 | www.powerelectronicsnews.com 57
